Unlike copyrights or patents, trademark registration rights can last indefinitely if the owner continues to use the mark to identify goods or services.
The term of a federal trademark registration is ten years, with ten-year renewal terms. However, between the fifth and sixth year after the date of initial trademark registration, you must file an "affidavit of use" and pay an additional fee to keep the registration alive. You must also file an affidavit and pay a fee within a year before the end of every ten-year period.
If an affidavit is missed, the registration is canceled. However, you may file the affidavit within a grace period of six months after the end of the sixth or tenth year, with payment of an additional fee.